<template>
  <el-breadcrumb class="app-breadcrumb" separator="/">
    <transition-group name="breadcrumb">
      <el-breadcrumb-item v-for="(item,index) in levelList" :key="item.path">
        <span v-if="item.redirect==='noRedirect'||index==levelList.length-1" class="no-redirect">{{ item.meta.title }}</span>
        <a v-else @click.prevent="handleLink(item)">{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
import pathToRegexp from 'path-to-regexp'

export default {
  data() {
    return {
      levelList : null
    }
  },
  watch : {
    $route( route ) {
      // if you go to the redirect page, do not update the breadcrumbs
      if ( route.path.startsWith( '/redirect/' ) ) {
        return
      }
      this.getBreadcrumb()
    }
  },
  created() {
    this.getBreadcrumb()
  },
  methods : {
    getBreadcrumb() {
      // only show routes with meta.title
      let matched = this.$route.matched.filter( item => item.meta && item.meta.title )
      const first = matched[0]

      if ( !this.isDashboard( first ) ) {
        matched = [{ path : '/', meta : { title : '趣立科技' }}].concat( matched )
      }

      this.levelList = matched.filter( item => item.meta && item.meta.title && item.meta.breadcrumb !== false )
    },
    isDashboard( route ) {
      const name = route && route.name
      if ( !name ) {
        return false
      }
      // return name.trim().toLocaleLowerCase() === 'Dashboard'.toLocaleLowerCase()
      return name.trim().toLocaleLowerCase() === 'Login'.toLocaleLowerCase()
    },
    pathCompile( path ) {
      // To solve this problem https://github.com/PanJiaChen/vue-element-admin/issues/561
      const { params } = this.$route
      var toPath = pathToRegexp.compile( path )
      return toPath( params )
    },
    handleLink( item ) {
      const { redirect, path } = item
      if ( redirect ) {
        this.$router.push( redirect )
        return
      }
      this.$router.push( this.pathCompile( path ) )
    }
  }

}
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
  display: inline-block;
  font-size: 14px;
  line-height: 50px;
  margin-left: 8px;

  .no-redirect {
    color: #97a8be;
    cursor: text;
  }
}
</style>
